South Korean and U.S. naval forces are reported to have begun joint drills in waters off the Korean peninsula.

South Korean defense officials are characterizing the latest military exercise as routine and purely defensive in nature. North Korea does not view it that way.

Referencing the maritime drills in the South, North Korea is calling on Seoul to stop “hostile acts and military provocations” to avoid a permanent closure of the now idled industrial zone at Kaesong, which is the two countries' only joint venture project.

South Korean officials Monday decried Pyongyang linking defense exercises to the fate of the civil factory complex in the North.

According to South Korea's semi-official Yonhap news agency, the drills began with an anti-submarine exercise on Monday in the Yellow Sea, a week after the conclusion of the annual Foal Eagle combined and joint unit tactical field training exercise on the Korean peninsula.

North Korea strongly objected to the previous round of military maneuvers, citing it as a prelude to an invasion. Pyongyang threatened to launch a nuclear attack.

Speaking to reporters in Seoul, Ministry of National Defense spokesman Kim Min-seok was asked about the participation in the exercise of the U.S. Navy's Nimitz super carrier and its strike force.

Kim said the nuclear-powered carrier comes to South Korea annually, noting it last visited in June of 2012, to participate in strategic training.

The spokesman declined to reveal the timing for this latest exercise at sea.

The U.S. navy says the carrier's strike group, which arrived in the 7th Fleet's area of responsibility last Friday, includes guided missile destroyers and a guided missile cruiser.

According to a U.S. Navy news release, the group “will conduct exercises and port visits to enhance maritime partnerships and promote peace and stability in the Indo-Asia-Pacific region along with its allies.”

The news release quotes Carrier Strike Group 11's commander, Rear Admiral Michael White saying the U.S. group does not take the exercise "lightly".

The release makes no specific reference to the tension on the Korean peninsula.

South Korean domestic media said the maneuvers include Aegis-equipped destroyers, patrol aircraft and submarines from both countries.

South Korean President Park Geun-hye, Sunday began a six-day official trip to the United States.

The top agenda item for her meeting with President Barack Obama on Tuesday is North Korea's continuing development of ballistic missiles and nuclear weapons, which recently was accompanied by the bellicose rhetoric threatening war.

South Korean government officials say President Park is to explain to President Obama her pledge to strongly retaliate against North Korean provocations while leaving the door open for dialogue with Pyongyang to build trust and reduce tensions.

The two Koreas have no diplomatic relations. They fought to a stalemate in a devastating three-year civil war in the early 1950's.